A bright light bulb

While shopping for LED strip lights, smart lights, or regular light bulbs, you’ll likely see mention of “lumens” or “lm” somewhere on the packaging or in the marketing materials. But what are lumens? We shed some light on the subject.

Lumens Are a Measure of Brightness

A lumen is a scientific unit that represents the visible light output of a light source. The brighter the light source, the more lumens it produces. The measurement of lumens is weighted and adjusted based on how humans perceive light.

So, for example, if you compare one light bulb that outputs 900 lumens and one that outputs 2000 lumens, the 2000 lumen bulb will be brighter than the 900-lumen bulb. The more lumens a light bulb emits, the brighter the bulb.

A light efficiency chart by bulb type.
Different bulb types produce more lumens while using fewer watts. Alhovik/Shutterstock.com

This means a good measurement for light bulb efficiency is lumens per watt (lm/W). A typical 100-watt incandescent bulb uses 100 watts of power and outputs about 1,600 lumens. Meanwhile, a 14-17 watt LED bulb can also output about 1,600 lumens. That means you’re getting more light for less power, which saves you money on your electricity bill.

The same principle applies to any type of lighting device: smart bulbs, LED light strips, or otherwise. The more lumens emitted, the brighter the output device.

The Best Smart Light Bulbs of 2022

Best Smart Bulb Overall
Philips Hue White and Color Ambiance
Best Budget Smart Bulb
Wyze Bulb
Best Outdoor Smart Bulb
Ring Wired Floodlight
Best Smart Bulb For Google Assistant
C by GE
Best Smart Bulb for Amazon Alexa
Sengled Smart Bulb
Best Smart Bulb for Apple HomeKit
WiZ Connected Color
Best Color Smart Bulb
Lifx Color
Best Wi-Fi Smart Bulb
Sengled Smart Wi-Fi LED Light Bulb
Best Bluetooth Smart Bulb
Govee LED Smart Light Bulbs

Understanding The Lighting Facts Label

For almost 100 years, people primarily used incandescent bulbs for lighting at home, and that allowed us to compare relative brightness by how much power each bulb used.

For example, you’d buy a “60-watt bulb” or a “100-watt bulb.” With the invention of radically more efficient lighting options such as LED bulbs that might only consume 15 watts but output as much as a 100-watt incandescent bulb, consumers needed a new way of comparing different lighting technologies.

An example US "Lighting Facts" Label

To solve this problem, the U.S. Federal Trade Commission instituted a requirement that the packaging for any light bulbs sold in the US must carry a “Lighting Facts” label. This label shows the bulb’s brightness in lumens, its estimated yearly energy cost, its lifespan, and its color temperature.

Other countries have similar labels that show light intensity or energy efficiency, such as the BEE Star Label in India.

You can now compare bulbs or other light sources by their brightness in lumens instead of relying on a general understanding of how much light a certain wattage of bulb should produce. It’s a vast improvement over the old ways. And, with energy-efficient bulbs getting cheaper, smarter, and more versatile all the time, it’s an exciting time to light up your life. Have fun!

The Best LED Strip Lights of 2022

Best Smart Strip Lights Overall
Govee 65.6ft LED Strip Lights
Best Budget
TJoy 50ft Smart LED Strip Lights
Best Waterproof LED Strip
Hitlights Waterproof White LED Light Strip
Best for Alexa
Cozylady 50ft Alexa LED Strip Lights
Best LED Strip Light for Google Assistant
Philips Hue Lightstrip
Profile Photo for Benj Edwards Benj Edwards
Benj Edwards is a former Associate Editor for How-To Geek. Now, he is an AI and Machine Learning Reporter for Ars Technica. For over 15 years, he has written about technology and tech history for sites such as The Atlantic, Fast Company, PCMag, PCWorld, Macworld, Ars Technica, and Wired. In 2005, he created Vintage Computing and Gaming, a blog devoted to tech history. He also created The Culture of Tech podcast and regularly contributes to the Retronauts retrogaming podcast.
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